ELECTRICITY is not an inexplicable miracle. It’s the result of a complex series of chemical reactions and mechanical processes that we have turned to the purpose of wringing energy from nature. It’s a brilliant achievement except for one issue: Our main sources of fuel destroy the planet when we use them, and they are running out anyway. The situation is dire but not irreparable. We know that there is enough energy from clean, renewable resources on our planet to easily give us all the power we need. We just have to harness it.